Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 769)

Viewfinder Information Display
Electronic Level
Grid
Information Display in Viewfinder
Electronic Level
Displays an electronic level at the top of the viewfinder when the shutter button is pressed
halfway. Also available in vertical shooting.
1.
Select [ : Viewfinder display].
2.
Select [Electronic level].
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